Theoretically, light transmission losses as low as 0.001 dB/km are possible in optical fibres made from heavy metal fluoride glasses. One reason this has not yet been achieved is scattering due to bubbles in the glass. Such bubbles can be reduced in size, if not completely eliminated, by heat treatment of the glass preform before fibre drawing.
Origin
Telecom Australia Research Labs, Victoria
Journal Title
J Non-Cryst Solids 95-96 1987 625-632
Sector
Glass Fibre
Class
GF 656